POLYESTER CONJUGATE FIBER, METHOD FOR PRODUCING THE SAME AND WOVEN OR KNIT FABRIC

PROBLEM TO BE SOLVED: To provide a polyester conjugate fiber having good appearance with little color density difference between fibers even by dyeing after blending with a polyethylene terephthalate fiber and imparting a woven or knit fabric with extremely high stretchability. SOLUTION: The conjugate fiber is a side-by-side conjugate fiber composed of (A) a block copolymer having high intrinsic viscosity and composed of a polytetramethylene terephthalate component and a polyoxytetramethylene glycol component and (B) a polyethylene terephthalate having low intrinsic viscosity and a viscosity difference of ≥0.5 from the copolymer A. The conjugate fiber has a Young's modulus of 20-60 cN/dtex and crimps to develop a cloth shrinkage of ≥40% in the form of a woven or knit fabric. The conjugate fiber is produced by ejecting a composite flow composed of two kinds of molten streams having a viscosity difference of ≥0.5 through an ejection hole inclined relative to an axis perpendicular to the spinneret surface at an angle of 10-45° toward the side of the high-viscosity polymer. COPYRIGHT: (C)2006,JPO&NCIPI